Castering Wheel Assembly for Rotary Mowers

Abstract

A castering wheel assembly comprising of a vertical shaft for caster, a horizontal wheel-mount standard, an axle pivotally attached to the standard, two wheels; with one wheel at each end of the axle arranged such that when the wheel assembly is attached to a rotary mower apparatus, the apparatus will follow straight on a side slope. Two embodiments of a mower apparatus comprising a mower deck and two wings, with a plurality of rear wheels mounted behind the mower deck(s) and two castering wheel assemblies mounted ahead of the mower deck such that the mower deck(s) ride along the ground. A trailing or offset floating hitch member is pivotally attached at one end to the front wheel assembly of the center mower deck and pivotally attached at an opposite end to a tractor allowing the mower deck(s) to float with respect to the tractor to follow contours on the ground.

I claim: 
     
         1 . A castering wheel assembly adapted for attachment to a rotary mower apparatus to allow travel along a side slope in an operating travel direction, the assembly comprising;
 a vertical shaft for caster;   a horizontal wheel mount standard;   an axle pivotally attached to the wheel standard;   and two wheels;   wherein each wheel is attached to the first and second end of the axle; and   wherein the wheels pivot about a substantially horizontal longitudinal wheel-rocking axis oriented substantially parallel to the operating travel direction.   
     
     
         2 . The castering wheel assembly of  claim 1  wherein the wheels are arranged such that the distance between the centers of the wheels is greater then one-half the distance between the pivot point on the axle and the running ground surface. 
     
     
         3 . The castering wheel assembly of  claim 1  wherein the wheels run perpendicular to the running ground surface when on a side slope. 
     
     
         4 . The castering wheel assembly of  claim 1  wherein the load on the caster axis stays between the centers of the wheels when on a side slope. 
     
     
         5 . A rotary mower apparatus adapted for attachment to a tractor for towing along the ground in an operating travel direction, the apparatus comprising;
 a central mower deck and right and left wing mower decks pivotally attached to respective right and left sides of the central mower deck;   a plurality of rear wheels mounted behind the mower decks and at least two front wheels mounted to the front end of the central mower deck such that the mower decks ride along the ground on the wheels;   a cutting blade element rotatably mounted under each mower deck so as to rotate about right, left, and central substantially vertical blade axis;   a floating hitch member pivotally attached to the front wheel assembly of the central mower deck and adapted for pivotal attachment at a tow end thereof to the tractor allowing the floating hitch member and front wheel assembly and mower decks to float with respect to the tractor to follow contours of the ground;   a drive adapted for connection to the tractor and operative to transfer power from the tractor to rotate the cutting blade element;   wherein the central mower deck is supported at the front end thereof by a first and second front castering wheel assembly attached to the first and second ends of a substantially horizontal cross member, wherein the cross member is attached to the front end of the central mower deck by a front parallel linkage attached to each side of the front end of the central mower deck;   wherein each castering wheel assembly comprises of a vertical shaft for caster; a horizontal wheel mount standard; an axle pivotally attached to the wheel standard; and two wheels; wherein each wheel is attached to the first and second end of the axle; and   wherein the wheels are pivotable about a substantially horizontal longitudinal wheel-rocking axis oriented substantially parallel to the operating travel direction.   
     
     
         6 . The apparatus of  claim 5  wherein the load on the caster axis of the castering wheel assembly stays between the centers of the wheels when on a side slope. 
     
     
         7 . The apparatus of  claim 5  wherein the wheels of the castering wheel assembly run perpendicular to the running ground surface when on a side slope. 
     
     
         8 . The apparatus of  claim 5  wherein each wheel of the castering wheel assembly is arranged such that the distance between the centers of the wheels is greater then one-half the distance between the pivot point on the axle and the running ground surface. 
     
     
         9 . The apparatus of  claim 5  wherein the central mower deck is supported at the rear end thereof by a dual wheel system comprising two sets of dual rear wheels;
 wherein each wheel in a set is attached to first and second end of a substantially horizontal rear axle; 
 wherein the two axles are pivotally attached to a walking beam standard; 
 wherein the wheels are pivotable about a substantial horizontal longitudinal wheel-rocking axis oriented substantially parallel with the operating travel direction; and 
 wherein the walking beam standard is pivotally attached at the center to the rear cross member about a substantially horizontal rear walking axis oriented substantially parallel with the operating travel direction. 
 
     
     
         10 . The apparatus of  claim 9  wherein the rear cross member is connected to the central mower deck by a pair of rear parallel linkages that are connected to the front parallel linkages by connecting rods; and
 wherein an actuator operates to move the front and rear wheels up and down in concert, and the caster axes of the front wheels are maintained substantially vertical. 
 
     
     
         11 . A rotary mower apparatus adapted for attachment to a tractor for towing along the ground in an operating travel direction, the apparatus comprising;
 a central mower deck and right and left wing mower decks pivotally attached to respective right and left sides of the central mower deck;   a plurality of rear wheels mounted behind the mower decks and at least two front wheels mounted to the front end of the central mower deck such that the mower decks ride along the ground on the wheels;   a cutting blade element rotatably mounted under each mower deck so as to rotate about right, left, and central substantially vertical blade axis;   a floating hitch member pivotally attached to the front wheel assembly of the central mower deck, so as to pivot about a substantially vertical hitch axis, and adapted for pivotal attachment at a tow end thereof to the tractor about a substantially vertical tow axis and wherein the floating hitch member is pivotally attached to the front wheel assembly of the central mower deck, so as to pivot about a substantially horizontal hitch axis oriented transversely to the floating hitch member and adapted for attachment at the tow end to the tractor attachment adaptor that provides a substantially horizontal longitudinal tow axis oriented substantially parallel to the operating travel direction, and a substantially horizontal transverse tow axis oriented substantially perpendicular to the operating travel direction, the attachments further allowing the floating hitch member and mower decks to float with respect to the tractor to follow contours of the ground;   a drive adapted for connection to the tractor and operative to transfer power from the tractor to rotate the cutting blade element;   a mower angle control operative to selectively pivot the floating hitch member about a vertical hitch axis with respect to the front wheel assembly and mower decks;   wherein the central mower deck is supported at the front end thereof by a first and second front castering wheel assembly attached to the first and second ends of a substantially horizontal cross member;   wherein the cross member is attached to the front end of the central mower deck by a front parallel linkage attached to each side of the front end of the central mower deck;   wherein each front castering wheel assembly comprising a vertical shaft for castering; a horizontal wheel mount standard; an axle pivotally attached to the wheel standard; and two wheels;   wherein each wheel is attached to the first and second end of the axle; and   wherein the wheels are pivotable about a substantially horizontal longitudinal wheel-rocking axis oriented substantially parallel to the operating travel direction.   
     
     
         12 . The apparatus of  claim 11  wherein each wheel of the castering wheel assembly is arranged such that the distance between the centers of the wheels is greater then one-half the distance between the pivot point on the axle and the running ground surface. 
     
     
         13 . The apparatus of  claim 11  wherein the wheels of the castering wheel assembly run perpendicular to the running ground surface when on a side slope. 
     
     
         14 . The apparatus of  claim 11  wherein the load on the caster axis of the castering wheel assembly stays between the centers of the wheels when on a side slope. 
     
     
         15 . The apparatus of  claim 11  wherein the central mower deck is supported at the rear end thereof by a dual wheel system comprising two sets of dual rear wheels;
 wherein each wheel in a set is attached to first and second end of a substantially horizontal rear axle; 
 wherein the two axles are pivotally attached to a walking beam standard wherein each wheel is pivotable about a substantial horizontal longitudinal wheel-rocking axis oriented substantially parallel with the operating travel direction; and 
 wherein the walking beam standard is pivotally attached at the center to the rear cross member about a substantially horizontal rear walking axis oriented substantially parallel with the operating travel direction. 
 
     
     
         16 . The apparatus of  claim 15  wherein the rear cross member is connected to the central mower deck by a pair of rear parallel linkages that are connected to the front parallel linkages by connecting rods; and
 wherein an actuator operates to move the front and rear wheels up and down in concert, and the caster axes of the front wheels are maintained substantially vertical. 
 
     
     
         17 . A rotary mower apparatus adapted for attachment to a tractor for towing along the ground in an operating travel direction, the apparatus comprising;
 a central mower deck and right and left wing mower decks pivotally attached to respective right and left sides of the central mower deck;   a plurality of rear wheels mounted behind the mower decks and at least two front wheels mounted to the front end of the central mower deck such that the mower decks ride along the ground on the wheels;   a cutting blade element rotatably mounted under each mower deck so as to rotate about right, left, and central substantially vertical blade axis;   a floating hitch member pivotally attached to the front wheel assembly of the central mower deck, so as to pivot about a substantially vertical hitch axis, and adapted for pivotal attachment at a tow end thereof to the tractor about a substantially vertical tow axis and wherein the floating hitch member is pivotally attached to the front wheel assembly of the central mower deck, so as to pivot about a substantially horizontal hitch axis oriented transversely to the floating hitch member and adapted for attachment at the tow end to the tractor attachment adaptor that provides a substantially horizontal longitudinal tow axis oriented substantially parallel to the operating travel direction, and a substantially horizontal transverse tow axis oriented substantially perpendicular to the operating travel direction, the attachments further allowing the floating hitch member and mower decks to float with respect to the tractor to follow contours of the ground;   a drive adapted for connection to the tractor and operative to transfer power from the tractor to rotate the cutting blade element; wherein the drive comprises; gearboxes, drive shafts, universal joints, and double universal joints;   a mower angle control comprising a hydraulic actuator and a bell crank fixedly attached to the vertical shaft operative to selectively pivot the floating hitch member about a vertical hitch axis with respect to the front wheel assembly of the central mower deck;   wherein the vertical hitch axis intersects the horizontal hitch axis at a point coincidental with the vertical shaft and this point is located substantially in the center of the double universal joint;   wherein the location of the vertical hitch axis at the center of a double universal joint allows for proper operation of the drive when the mower angle control is used to vary the offset of the rotary mower apparatus;   wherein the horizontal hitch axis intersects the vertical hitch axis at a point above the hitch standard and the vertical shaft and this point is located substantially in the center of a double universal joint; and   wherein the location of the horizontal hitch axis at the center of the double universal joint allows proper operation of the drive when the hitch pivots about the horizontal hitch axis with respect to the attached front wheel assembly of the central mower deck   
     
     
         18 . The apparatus of  claim 17  wherein the drive is substantially aligned with the floating hitch member. 
     
     
         19 . The apparatus of  claims 17  wherein the rotary mower apparatus has a single mower deck.